1. Field of the Invention
The present invention relates to an improved articulator having a base including a support for a model of a lower jaw, said support carried by said base, having a support for a model of an upper jaw, which support is mounted to pivot around a lateral shaft extending within a fixture which is universally movable relative to said base, having further a pressing means including a spring and acting along an axis extending perpendicularly to said lateral shaft and operative to press said base and said fixture at their respective supporting surfaces together such that due to a form closed abutment of base and fixture at said supporting surfaces a defined relative position between base and fixture is reached, which said pivotable support for a model of an upper jaw is movably guided relative to said base by means of a cam and a cam follower, which said support for a model of an upper jaw is carried in a pivoting arm supported by means of said lateral shaft in a bearing pedestal, said bearing pedestal and said pivoting arm forming together said fixture.
2. Description of the Prior Art
An articulator of the kind set forth above is disclosed in the Swiss patent specification No. 412 194. If the clamping means of this known articulator is in a released state, the fixture and base thereof will be moved by a spring arranged within the clamping means out of a respective form closed locked position such that the fixture may be spherically moved relative to the base. Such allows obviously a movement along the three spatial axes as well as a combination of these movements; however, a natural chewing movement (articulation) cannot be simulated because the lower jaw is obviously not mounted to the upper jaw via a spherical hinge. In order now to provide such articulators allowing the simulation of the natural chewing movements several developments have been made and disclosed such as disclosed for instance in the Swiss patent specification Nos. 346 319, 350 757; 437 629; 515 031 and 604 675. All these named articulators referred to above have in common the provision of two sockets of respective ball-and-socket joints located on a lateral axis and the distance between the two joint sockets is claimed to correspond to the distance of the natural joint sockets of human beings. According to an embodiment disclosed mentioned distance between the two sockets amounts to 108 mm. Conclusively, the articulators disclosed are quite bulky, necessitate due to the requisite precision an expensive steel construction, a meeting of close tolerances and, therefore, feature a relatively complicated and expensive structural conception. The above described drawbacks of the articulators of the other design are claimed to be overcome by the above referred articulator in accordance with the Swiss patent specification No. 412 194.